SYDNEY, Australia — The 36-year-old cold case had always been memorable: Lynette Dawson, a nurse and child care worker, vanished from a coastal suburb of Sydney, leaving two young daughters behind. Days later, her husband, an athlete turned teacher, moved in with the couple’s 16-year-old babysitter.

SYDNEY, Australia — The 36-year-old cold case had always been memorable: Lynette Dawson, a nurse and child care worker, vanished from a coastal suburb of Sydney, leaving two young daughters behind. Days later, her husband, an athlete turned teacher, moved in with the couple’s 16-year-old babysitter.

She was his student, and they were having an affair.

She was his student, and they were having an affair.

These details and others are at the center of “Teacher’s Pet,” a podcast whose investigative journalism has catapulted it to 27 million downloads and the top of the charts for true crime.

These details and others are at the center of “Teacher’s Pet,” a podcast whose investigative journalism has catapulted it to 27 million downloads and the top of the charts for true crime.

Now, after almost four decades of speculation, there’s been a break in the case. The police have arrested Chris Dawson, 70, and on Thursday he was charged in Sydney with the homicide of his wife. It was an “important step forward” toward justice for the Dawson family, said Mick Fuller, the New South Wales police commissioner.

Now, after almost four decades of speculation, there’s been a break in the case. The police have arrested Chris Dawson, 70, and on Thursday he was charged in Sydney with the homicide of his wife. It was an “important step forward” toward justice for the Dawson family, said Mick Fuller, the New South Wales police commissioner.

The criminal charge has vindicated the suspicions of those who believe that Mr. Dawson killed his wife in order to be with his girlfriend. Greg Simms, Mrs. Dawson’s brother, told The Australian the family was “completely over the moon” with the development.

The criminal charge has vindicated the suspicions of those who believe that Mr. Dawson killed his wife in order to be with his girlfriend. Greg Simms, Mrs. Dawson’s brother, told The Australian the family was “completely over the moon” with the development.

Since his wife’s disappearance in 1982, Mr. Dawson has maintained his innocence, saying that she abandoned her family. On Wednesday, his family said it was “disappointed” with the decision, adding, “We have no doubt whatsoever that Chris will be found not guilty as he is innocent.”

Since his wife’s disappearance in 1982, Mr. Dawson has maintained his innocence, saying that she abandoned her family. On Wednesday, his family said it was “disappointed” with the decision, adding, “We have no doubt whatsoever that Chris will be found not guilty as he is innocent.”

But the podcast has also sparked a conversation for women and men who came of age in the 1980s about a pervasive culture of impunity, which enabled Mr. Dawson to date his student.

But the podcast has also sparked a conversation for women and men who came of age in the 1980s about a pervasive culture of impunity, which enabled Mr. Dawson to date his student.

He was a former rugby star with friends in law enforcement, a man’s man who had seemed to be untouchable in a country that elevates “mateship” to a national virtue. But as the podcast has become more popular, former high school students from the area — sometimes called “the insular peninsula” — have spoken out about how he seemed to fit into a larger pattern in which teachers exploited their positions to enter sexual relationships with students while many adults turned a blind eye.

He was a former rugby star with friends in law enforcement, a man’s man who had seemed to be untouchable in a country that elevates “mateship” to a national virtue. But as the podcast has become more popular, former high school students from the area — sometimes called “the insular peninsula” — have spoken out about how he seemed to fit into a larger pattern in which teachers exploited their positions to enter sexual relationships with students while many adults turned a blind eye.

Kate McAuley was one such teenager, at Beacon Hill Public School in the late 1980s, a time when she struggled with problems at home and felt like she was on the periphery. At 14, she said, she was targeted by a male teacher, who began asking her to stay after class and touching her inappropriately.

Kate McAuley was one such teenager, at Beacon Hill Public School in the late 1980s, a time when she struggled with problems at home and felt like she was on the periphery. At 14, she said, she was targeted by a male teacher, who began asking her to stay after class and touching her inappropriately.

Like Mr. Dawson, he was in a romantic relationship with another woman, one of his former students, Ms. McAuley said.

Like Mr. Dawson, he was in a romantic relationship with another woman, one of his former students, Ms. McAuley said.

“I just thought it was normal,” she said. “Now, looking back, it’s not O.K. None of it was O.K.”

“I just thought it was normal,” she said. “Now, looking back, it’s not O.K. None of it was O.K.”

The extent of the predation was “disgusting,” she said. “People were more worried about a man’s reputation than protecting women.”

The extent of the predation was “disgusting,” she said. “People were more worried about a man’s reputation than protecting women.”

Now, the silence is breaking. Angered by the lack of consequences and emboldened by the conversation around “Teacher’s Pet,” a class of women and men who grew up targeted by predatory teachers are sharing their stories and calling for accountability.

Now, the silence is breaking. Angered by the lack of consequences and emboldened by the conversation around “Teacher’s Pet,” a class of women and men who grew up targeted by predatory teachers are sharing their stories and calling for accountability.

“When a man in his 30s has any kind of intimate relationships with a girl who is 16, 17, that’s sexual assault,” said Robyn Wheeler, a former student at Cromer High School, where Mr. Dawson taught his family’s babysitter, Joanne Curtis, who was 16 at the time.

“When a man in his 30s has any kind of intimate relationships with a girl who is 16, 17, that’s sexual assault,” said Robyn Wheeler, a former student at Cromer High School, where Mr. Dawson taught his family’s babysitter, Joanne Curtis, who was 16 at the time.

Ms. Wheeler has led the charge to expose the extent of sexual abuse at the school in the 1980s, and alleged that at least six teachers were in relationships with students while she studied there. During an overnight trip for a sporting tournament, she said, teachers brought alcohol and encouraged girls to drink.

Ms. Wheeler has led the charge to expose the extent of sexual abuse at the school in the 1980s, and alleged that at least six teachers were in relationships with students while she studied there. During an overnight trip for a sporting tournament, she said, teachers brought alcohol and encouraged girls to drink.

“The environment was compounded by a lack of willingness by those in authority to exercise a duty of care,” she said, alleging that the Department of Education and the police had turned a blind eye.

“The environment was compounded by a lack of willingness by those in authority to exercise a duty of care,” she said, alleging that the Department of Education and the police had turned a blind eye.

Since the podcast’s release, with new clues unearthed by veteran investigative reporter Hedley Thomas, more people have come forward to share their experiences, and at least 20 teachers have been accused of misconduct. “Its been quite cathartic to be able to sit down with some of the people who have been victims and say, ‘You do realize you did nothing wrong,’” Ms. Wheeler said.

Since the podcast’s release, with new clues unearthed by veteran investigative reporter Hedley Thomas, more people have come forward to share their experiences, and at least 20 teachers have been accused of misconduct. “Its been quite cathartic to be able to sit down with some of the people who have been victims and say, ‘You do realize you did nothing wrong,’” Ms. Wheeler said.

“A woman’s life is not disposable like it was in the past,” said Susan Harris Rimmer, a law professor at Griffith University in Queensland. “I think institutions now have to prove their moral worthiness where they just didn’t before.”

“A woman’s life is not disposable like it was in the past,” said Susan Harris Rimmer, a law professor at Griffith University in Queensland. “I think institutions now have to prove their moral worthiness where they just didn’t before.”

A new police task force was formed in July to investigate these historical sexual assault allegations, The Australian reported. Ms. Wheeler said she had been working with the police investigation into allegations.

A new police task force was formed in July to investigate these historical sexual assault allegations, The Australian reported. Ms. Wheeler said she had been working with the police investigation into allegations.

For those following the case of Mrs. Dawson’s disappearance as it grew colder over the decades, the arrest was a shockingly tangible update. In 2001, a coroners’ inquest concluded that a “known” person had killed Mrs. Dawson. A second inquest in 2003 recommended that Mr. Dawson be charged in her death, but the director of public prosecutions declined to press charges, citing a lack of evidence.

For those following the case of Mrs. Dawson’s disappearance as it grew colder over the decades, the arrest was a shockingly tangible update. In 2001, a coroners’ inquest concluded that a “known” person had killed Mrs. Dawson. A second inquest in 2003 recommended that Mr. Dawson be charged in her death, but the director of public prosecutions declined to press charges, citing a lack of evidence.

The case stagnated until 2015, when the police opened another investigation, and in April, officials submitted a new evidence brief to the director of public prosecutions. In September, officials excavated the Dawsons’ former house in search of her body, to no avail.

The case stagnated until 2015, when the police opened another investigation, and in April, officials submitted a new evidence brief to the director of public prosecutions. In September, officials excavated the Dawsons’ former house in search of her body, to no avail.

The release of “Teacher’s Pet” in May rekindled public interest in the case — the podcast has topped charts in Australia, the United States and Canada, and won Australia’s most prestigious journalism award — and its popularity seemed to ramp up with developments in the case.

The release of “Teacher’s Pet” in May rekindled public interest in the case — the podcast has topped charts in Australia, the United States and Canada, and won Australia’s most prestigious journalism award — and its popularity seemed to ramp up with developments in the case.

On Wednesday, the police thanked the news media and the public for playing a role in the arrest, saying that while the attention was not “crucial,” the interest had helped them uncover new evidence. They will continue to search for Mrs. Dawson’s body.

On Wednesday, the police thanked the news media and the public for playing a role in the arrest, saying that while the attention was not “crucial,” the interest had helped them uncover new evidence. They will continue to search for Mrs. Dawson’s body.

The Dawsons lived in the Northern Beaches district, a suburb of Sydney known for its oceanfront real estate and wealthy residents — and as the original setting for Liane Moriarty’s novel turned TV show, “Big Little Lies,” which depicts domestic violence.

The Dawsons lived in the Northern Beaches district, a suburb of Sydney known for its oceanfront real estate and wealthy residents — and as the original setting for Liane Moriarty’s novel turned TV show, “Big Little Lies,” which depicts domestic violence.

“A lot of beautiful places in Australia have a bit of a dark side,” Ms. Harris Rimmer said.

“A lot of beautiful places in Australia have a bit of a dark side,” Ms. Harris Rimmer said.

Sitting at a cafe near Dee Why Beach in the district, Amber Cooper, a local resident, said that as a high school student in 2001, she remembers a phys-ed teacher being fired for inappropriate behavior. “Everyone knew he was a creep,” she said.

Sitting at a cafe near Dee Why Beach in the district, Amber Cooper, a local resident, said that as a high school student in 2001, she remembers a phys-ed teacher being fired for inappropriate behavior. “Everyone knew he was a creep,” she said.

Because of the #MeToo moment, she said, people are starting to speak up — even though some do not like talking about the problems under the neighborhood’s surface. “It’s a great area, but people don’t realize that the problems that happen in bad areas happen here,” she said.

Because of the #MeToo moment, she said, people are starting to speak up — even though some do not like talking about the problems under the neighborhood’s surface. “It’s a great area, but people don’t realize that the problems that happen in bad areas happen here,” she said.

More recent students, though, said the high schools here seem to be safer now.

More recent students, though, said the high schools here seem to be safer now.

Five minutes from the beach, Cromer High School, now named Cromer Campus, stands on a remote road surrounded by tall trees. At the soccer pitch across the street, a few students were waiting for a lesson. “I think it was such a long time ago, it doesn’t really affect anyone of our age,” said James Kain, a 21-year-old coach. He caught bits and pieces of the case through the news, but has never heard of any faculty misconduct at the high schools he attended in the Northern Beaches.

Five minutes from the beach, Cromer High School, now named Cromer Campus, stands on a remote road surrounded by tall trees. At the soccer pitch across the street, a few students were waiting for a lesson. “I think it was such a long time ago, it doesn’t really affect anyone of our age,” said James Kain, a 21-year-old coach. He caught bits and pieces of the case through the news, but has never heard of any faculty misconduct at the high schools he attended in the Northern Beaches.

“It’s a good place to grow up,” he said.

“It’s a good place to grow up,” he said.

But for those who remember Cromer High School during the 1980s, the experience left scars. Ms. McAuley said it made her certain that life was better outside of the Northern Beaches. “It made me want to find home, or the idea of home elsewhere,” she said. At 19, she moved away from Australia, vowing never to live here again.

But for those who remember Cromer High School during the 1980s, the experience left scars. Ms. McAuley said it made her certain that life was better outside of the Northern Beaches. “It made me want to find home, or the idea of home elsewhere,” she said. At 19, she moved away from Australia, vowing never to live here again.

“From the outside, I grew up in an idyllic environment,” she said. “The beaches are so beautiful, we have the sun, the great weather. But part of it was rotten.”

“From the outside, I grew up in an idyllic environment,” she said. “The beaches are so beautiful, we have the sun, the great weather. But part of it was rotten.”